﻿#include <linux/module.h>

#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/miscdevice.h>
#include <linux/kernel.h>
#include <linux/major.h>
#include <linux/mutex.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/stat.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/tty.h>
#include <linux/kmod.h>
#include <linux/gfp.h>
#include <asm/io.h>

#include "led_opr.h"

static volatile unsigned int *CCM_CCGR1                              ;
static volatile unsigned int *IOMUXC_SNVS_SW_MUX_CTL_PAD_SNVS_TAMPER3;
static volatile unsigned int *GPIO5_GDIR                             ;
static volatile unsigned int *GPIO5_DR                               ;

static int board_demo_led_init (int which) /* 初始化LED, which-哪个LED */       
{
    unsigned int val;

    //printk("%s %s line %d, led %d\n", __FILE__, __FUNCTION__, __LINE__, which);
    if (which == 0)
    {
        if (!CCM_CCGR1)
        {
            CCM_CCGR1                               = ioremap(0x20C406C, 4);
            IOMUXC_SNVS_SW_MUX_CTL_PAD_SNVS_TAMPER3 = ioremap(0x2290014, 4);
            GPIO5_GDIR                              = ioremap(0x020AC000 + 0x4, 4);
            GPIO5_DR                                = ioremap(0x020AC000 + 0, 4);
        }
        
        /* GPIO5_IO03 */
        /* a. 使能GPIO5
         * set CCM to enable GPIO5
         * CCM_CCGR1[CG15] 0x20C406C
         * bit[31:30] = 0b11
         */
        *CCM_CCGR1 |= (3<<30);
        
        /* b. 设置GPIO5_IO03用于GPIO
         * set IOMUXC_SNVS_SW_MUX_CTL_PAD_SNVS_TAMPER3
         *      to configure GPIO5_IO03 as GPIO
         * IOMUXC_SNVS_SW_MUX_CTL_PAD_SNVS_TAMPER3  0x2290014
         * bit[3:0] = 0b0101 alt5
         */
        val = *IOMUXC_SNVS_SW_MUX_CTL_PAD_SNVS_TAMPER3;
        val &= ~(0xf);
        val |= (5);
        *IOMUXC_SNVS_SW_MUX_CTL_PAD_SNVS_TAMPER3 = val;
        
        
        /* b. 设置GPIO5_IO03作为output引脚
         * set GPIO5_GDIR to configure GPIO5_IO03 as output
         * GPIO5_GDIR  0x020AC000 + 0x4
         * bit[3] = 0b1
         */
        *GPIO5_GDIR |= (1<<3);
    }
    
    return 0;
}

static int board_demo_led_ctl (int which, char status) /* 控制LED, which-哪个LED, status:1-亮,0-灭 */
{
    //printk("%s %s line %d, led %d, %s\n", __FILE__, __FUNCTION__, __LINE__, which, status ? "on" : "off");
    if (which == 0)
    {
        if (status) /* on: output 0*/
        {
            /* d. 设置GPIO5_DR输出低电平
             * set GPIO5_DR to configure GPIO5_IO03 output 0
             * GPIO5_DR 0x020AC000 + 0
             * bit[3] = 0b0
             */
            *GPIO5_DR &= ~(1<<3);
        }
        else  /* off: output 1*/
        {
            /* e. 设置GPIO5_IO3输出高电平
             * set GPIO5_DR to configure GPIO5_IO03 output 1
             * GPIO5_DR 0x020AC000 + 0
             * bit[3] = 0b1
             */ 
            *GPIO5_DR |= (1<<3);
        }
    
    }
    return 0;
}

static struct led_operations board_demo_led_opr = {
    .num  = 1,
    .init = board_demo_led_init,
    .ctl  = board_demo_led_ctl,
};

struct led_operations *get_board_led_opr(void)
{
    return &board_demo_led_opr;
}

